Might be a newbie question, but when you install the N55 mid pipe, does the absence of the stock secondary cats generate any diagnostic errors? Also, any ideas how this mod affects the results of emission tests?

No ecu errors, sensors are situated on the downpipes as for emissions, and if you are concerned re failing and emission test, just refit the midpipes with the secondary cats when it comes time down the track.....

Quote:

Originally Posted by Denso

All sounds good to me mate, lets hope that BMW get this in stock for me before ineed to do my next stint away. When you get the axle back i would appreciate your thoughts on that too

Swapped mine out yesterday at lunch. No real big differences noted though. It does sound a bit... deeper, the drone is still there around 2500-3k rpms (ish) but it's not as loud as before. I did notice a change in tone at WOT though that's hard to describe but... . It's almost like I can hear the exhaust gases flowing through the pipe now (like I said, hard to describe, lol).
All in all, if it gives me a few hp then I'd say it's a decent exhaust mod for the price. I do have to warn folks though... those aluminum bolts that hold the front of the chassis brace on WILL shear off if you're not careful ().

- Does the change of N55 to N54 midpipe cause any issues for the "Check Control" or should I have any problems for warranty?

Not sure about warranty but there are no sensors in or behind the mid-pipe so there won't be a CEL. A mechanic familiar with the N54 or 1M might notice the lack of secondary cats but I doubt most would notice just by looking underneath.

Quote:

Originally Posted by flavush

- On the videos I can't hear much difference. Does only the N55 midpipe sound much louder than stock N54 midpipe?

In my experience it's not much louder but the tone is deeper. More of a growl. I also noticed more of the "gurgle and pop" when off-throttle that I love. (Sounds more like my MINI off-throttle)

I've been reading this with interest and will be ordering my N55 midpipe. Thanks for posting your results, guys, progress needs these inputs.

Re: The M button; There are some conflicting reports on here which all appear credible to me, I think the thing we are missing is that all 1Ms round the world are not the same. We have already seen that some markets have two of the tailpipes plugged (China) and, believe me, there are many other differences in production cars to accommodate the different laws and tax regimes that the car manufacturers face.

In the UK we are taxed on CO emissions which is tested in the default mode when the car is turned on i.e. with M (or Sport on other cars) turned off. The manufacturers therefore put an emissions optimised tune into the car and only give us the "full beans" version on the M button.

In other markets this wouldn't be necessary so it is entirely feasible that some markets will show extra power from the M button while others won't.

We also have an R60 Mini Countryman S and it is especially noticeable on that, improved economy with the Sport off and power with it on.

So I think its likely that you're all correct.

Btw, I have been trying to find out if anyone is bringing Maddads into the UK, anyone know?

Maddads on an otherwise stock exhaust sound great! Nice bark on startup and a nice deep bellow on the gas, but not obnoxiously loud at all.

Yeah, they are strong those Maddads, I figured that if I would go just with a midpipe then I should better go with them and not N55 but it appeared to me impossible to find one here or import, just too much complications so I ended up with bringing N55 mids mated with Evolve Race rear muffler. If I could have the Maddads first maybe I would stick with the stock muffler cause Maddad "changes" the sound a lot more than the N55 does. In short, just midpipe swap Maddad is the better option, but together with any good sounding rear muffler then N55 is better unless you definitely want it as loud as possible.

After reading forums,decided to fit N55 mids. What a joy. Cold startup is a hoot with crackle and popping. The drone was driving me bonkers on long trips. Virtually disappeared and overall sound throughout is wonderful. Not excessive. Just a deeper growl and definitely more responsive from mid revs. A bargain bolt-on.

After reading forums,decided to fit N55 mids. What a joy. Cold startup is a hoot with crackle and popping. The drone was driving me bonkers on long trips. Virtually disappeared and overall sound throughout is wonderful. Not excessive. Just a deeper growl and definitely more responsive from mid revs. A bargain bolt-on.

^^^^^ This
Fitted mine today ,a well worth mod for little outlay,ordered it late Monday and got the call from dealer Wedensday morning.

No big difference in sound, I thing it is a bit deeper and noisier but my girlfriend most likely won t notice the difference... (haven t tried yet)
No faults as expected
I don t feel any difference in HP, better revving at high rpm´s.
I DO feel a huge difference in throttle response, less turbo lag and it feels more linear, I really like it.
Drone between 2100-2450 RPM is totally gone (actually it felt strange not to have it) but from 2500 to 2700 there is now a bit, nothing like before but still something.